The subject invention relates to switching regulators or DC-DC converters where the input source of voltage is substantially fixed and the regulator output voltage is maintained at a substantially constant level.
Switching regulators or DC-DC converters, sometimes referred to as switching mode power supply, are used to convert an input supply voltage from the input terminals to a desired output voltage through output terminals. The output voltage can be maintained to have a substantially constant magnitude.
The low loss components in switching regulators such as capacitors, inductors, power switches, and transformers are alternatively turned on and off to transfer power from the input terminal to the output terminal in discrete packets. Feedback control circuits coupled to the control-in terminals are used to regulate and control the power. In some applications, the output voltage can be adjusted externally to a desirable level through at least one resistor coupled to the feedback signal which is generated from the regulator output voltage.
Continuous Conduction Mode (CCM) and Discontinuous Conduction Mode (DCM) are the two typical operation modes in switching regulators. The subject invention is designed to operate in the CCM mode where the load is significant and the inductor current remains positive during the entire switching period.
In modern switching regulator or DC-DC converter design, one of the challenging tasks is to generate a feedback signal without using the output voltage. The number of control-in terminal PINs can therefore be reduced without having to be used to connect the feedback signal to the main controller. Additionally, some applications require that the regulator output voltage must be able to be externally adjustable.